Texas Instruments SN74CBTD3861DGVR

Overview

SN74CBTD3861DGVR from Texas Instruments is a 10-bit FET bus switch with integrated level-shifting capability, designed for bidirectional 5-V-to-3.3-V signal translation between logic domains. It features 5-Ω on-state resistance, TTL-compatible inputs, and single OE control enabling/disabling all ten channels simultaneously. It is used in mixed-voltage system interconnects such as memory expansion interfaces and processor peripheral buses.

For engineers reviewing the SN74CBTD3861DGVR datasheet, SN74CBTD3861DGVR pinout, SN74CBTD3861DGVR application, or SN74CBTD3861DGVR equivalent, key selection criteria include its guaranteed 5-Ω r_on, 0.35-ns propagation delay, ±1-µA I_I leakage, 4.5–5.5-V V_CC operation, and TVSOP-24 package thermal performance (θ_JA = 86°C/W).

Technical Context

This device implements a passive FET-based transmission gate architecture with integrated input diodes to V_CC, enabling reliable 5-V-to-3.3-V unidirectional level shifting without external components. Its single OE input controls all ten A/B channel pairs simultaneously, supporting synchronous bus isolation in high-speed digital systems.

The switch operates with minimal propagation delay due to low on-resistance and is specified for –40°C to 85°C ambient operation. Input clamp current (–50 mA) and absolute maximum V_I (–0.5 V to 7 V) support robust ESD tolerance and overvoltage resilience during hot-swap or power sequencing events.

Key Specifications

Pinout & Package

SN74CBTD3861DGVR is housed in a 24-pin TVSOP (Thin Very Small Outline Package) with 0.4-mm lead pitch, 6.9-mm width, and 1.2-mm max height - optimized for high-density PCB layouts while maintaining manufacturability with standard reflow profiles (MSL Level-1).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bus-switching applications.

Compared with SN74CBTD3861DGVR, SN74CBT3861PWR offers identical functionality in a thermally similar TSSOP package, while SN74LVC1G3157DCKR serves fundamentally different single-channel, non-level-shifting roles - making it unsuitable for direct replacement in 10-bit bus applications.

Availability

SN74CBTD3861DGVR is available at Aetrix Electronics and suitable for industrial automation interfaces, memory subsystems, and legacy-to-modern voltage bridging requiring stable component supply and long-lifecycle support.

Supply support for SN74CBTD3861DGVR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of expertise in high-reliability interface ICs and industrial-grade timing products.

The SN74CBTD3861DGVR belongs to TI's 74CBT logic family, engineered specifically for high-speed, low-distortion bus switching in mixed-voltage digital systems - targeting industrial control, communications infrastructure, and test equipment.

FAQ

What is the maximum continuous current per channel for SN74CBTD3861DGVR?

The SN74CBTD3861DGVR supports up to 128 mA continuous channel current, as specified in its Absolute Maximum Ratings. This rating applies to each A/B path under steady-state conduction with proper thermal management. The device maintains 5-Ω typical on-resistance across this range, ensuring minimal voltage drop and self-heating within safe limits for TVSOP-24 packaging.

Does SN74CBTD3861DGVR support bidirectional level shifting between 3.3-V and 5-V domains?

SN74CBTD3861DGVR is explicitly designed for unidirectional 5-V-to-3.3-V level shifting via its integrated input diode to V_CC. It does not support reverse-direction (3.3-V-to-5-V) translation. When driven from the B side, the device operates as a standard bidirectional switch without level-shifting functionality - output voltage follows input voltage within the same domain.

Can SN74CBTD3861DGVR be used without external pull-up or pull-down resistors on the OE pin?

Yes - SN74CBTD3861DGVR has no internal pull-up or pull-down on OE, so external biasing is required for deterministic operation. TI recommends tying OE directly to GND (for always-on) or V_CC (for always-off), or using a controlled logic driver. Floating OE violates Recommended Operating Conditions and may cause undefined switching behavior or increased ICC.

What is the thermal resistance (θ_JA) of SN74CBTD3861DGVR, and how does it affect thermal design?

SN74CBTD3861DGVR has a junction-to-ambient thermal resistance (θ_JA) of 86°C/W in its TVSOP-24 package. At full 128-mA channel current and 5-V V_CC, worst-case power dissipation (~0.8 W) results in ~69°C junction rise above ambient. Designers must ensure PCB copper area and airflow keep ambient temperature ≤+85°C to maintain reliable operation within the device's rated range.

Is SN74CBTD3861DGVR RoHS compliant and lead-free?

Yes, SN74CBTD3861DGVR is RoHS compliant and features NiPdAu (NIPDAU) lead finish, as confirmed in TI's Package Option Addendum. It meets JEDEC MSL Level-1 (unlimited floor life) and is qualified for Pb-free reflow soldering at peak temperatures up to 260°C, supporting modern environmental compliance requirements for industrial and commercial electronics.